Display systems for headgear are known wherein a cathode ray tube is mounted on a helmet to project an image. One such display system is shown in U.S. Pat. No. 3,059,519 wherein the image from the cathode ray tube is projected to an image splitter for right and left eye channels providing a binocular effect. In each of the eye channels a first mirror is mounted on a helmet extension that projects outwardly in front of the user's forehead at a distance therefrom. The first mirror reflects the image from the image splitter to a second mirror that is mounted on a second extension of the helmet that abuts the forehead of the user. The second mirror reflects the image from the first mirror onto a third mirror mounted on the first extension of the helmet so that the image may be viewed by the user. The display system also includes a lens disposed in the optical path to project the image at infinity. Another such display system is shown in U.S. Pat. No. 3,787,109 wherein a partially transparent visor having an inner surface that is shaped as a paraboloid of revolution is mounted on the helmet and wherein a light source is positioned to project from the visor's focal point so that the projected image appears located at infinity, the image being superimposed on the scene viewed through the visor. U.S. Pat. No. 3,833,300 shows another such display system wherein a dual parabolic visor is slidably secured to the helmet and wherein the cathode ray tube projects an image at the focal point of each of the visor's parabola.
Another type of head mounted display system is shown in U.S. Pat. No. 3,170,979 wherein a harness mounts the display system on a user's head. The display system includes a cathode ray tube, the image from which is magnified by a lens assembly and displayed on a see-through reflecting surface that is positioned in the line of sight of the user.
Other display systems, integrally formed into a goggle, or mask are shown in the following. U.S. Pat. No. 4,361,384 shows a goggle or mask having a see-through optical element to permit the simultaneous viewing of an intensified TV image and an object or scene. The goggle or mask is held in place by retaining gear which surrounds the head and cups under the chin. U.S. Pat. No. 3,712,714 shows a diver's mask having status indicators such as a clock and compass mounted to the diver's mask and reflected by a pair of mirrors so as to be viewed by the diver. These prior display systems are cumbersome, bulky and unsuitable for consumer type applications wherein the displayed information must be projected in a manner so as not to interfere with the user's normal field of view.